1. Field of the invention
The present invention relates to a cleaning device for a Scorotron type electrostatic charger which is used in an image forming apparatus such as a copying machine.
2. Description of the Prior Art
A Scorotron type electrostatic charger of an image forming apparatus such as a copying machine is such that grid wires are provided between a photosensitive body and a corona discharge wire and a fixed potential is given to the photosensitive body with high voltage applied by the corona discharge wire. Both the wires on the electrostatic charger may get soiled due to splashed toner and pieces of paper while copying is continued in such a copying machine. The soiling may cause the surface potential of the photosensitive body to fluctuate and in line therewith the image density may change. For this reason, a cleaning device for an electrostatic charger was developed (Japanese Patent Publication NO. Sho-63-24561).
FIG. 5 is a simulative diagram showing the outline configuration in an example of cleaning devices A' for the conventional electrostatic chargers.
As shown in FIG. 5, a cleaning device A' for a conventional electrostatic charger 31, in which a wire cleaning member 33 for cleaning discharge wires 32 and a grid cleaning member 35 for cleaning grid wires 34 are provided, is of such a structure that both the members 33 and 35 are integrated together. And it is composed so that the discharge wires 32 and grid wires 34 are simultaneously cleaned by reciprocating both the members 33 and 35 simultaneously in the extending direction of the discharge wires 32 and grid wires 34 by a drive unit (not illustrated). And in FIG. 5, 36 indicates the photosensitive body.
As with a cleaning device A' for the conventional electrostatic charger 31 the discharge wires 32 and grid wires 34 are simultaneously cleaned, the drive load of the cleaning members was remarkably heavy, thereby resulting in an increase of the production cost of an apparatus and an increase of the consumption power thereof.